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A seven-month journey is about to end with "seven minutes of terror" as Nasa's Perseverance rover prepares for an intense landing.

The six-wheeled robot is fast approaching Mars after a 470-million-km (292-million-mile) journey from Earth.

But before it can get on with its important mission, Perseverance has got to land itself down safely on the Red Planet - something that is really difficult and risky to do.

The entry, descent and landing (EDL) phase of a Mars mission is often referred to as "seven minutes of terror," because it all happens faster than radio signals can reach Earth from Mars.

That means the spacecraft is on its own once it enters the Martian atmosphere.

The name Perseverance was chosen by Alexander Mather, a 13-year-old student from Virginia, in the US, who took part in Nasa's competition to name the robot.

If the rover successfully touches down on the surface, it has an amazing opportunity to find signs of life that once lived on the planet.

Never has a science mission gone to Mars with such an advanced set of equipment and never has a robot been sent to such a promising a location in terms of finding past life.

If all goes to plan, Perseverance will land on the red planet at a place called Jezero Crater.

Satellite images suggest that the crater - which was made by a meteorite - was once full of a giant lake of water which could have been full of microscopic life.

The lake dried up over time and Perseverance will drill the rock inside the crater, with the most promising samples packaged up to return to earth on future missions.

• Contact with atmosphere: 20:48 GMT (8:48 PM)

• Parachute deployed: 20:52 GMT (8:52 PM)

• Powered descent: 20:54 GMT (8:54 PM)

• Wheels down: 20:55 GMT (8:55 PM)

"Before we can get that surface mission going, we have to land on Mars and that is always a challenging feat," said Matt Wallace, Nasa's deputy project manager for Perseverance.

"This is one of the most difficult manoeuvres we do in the space business. Almost 50% of the spacecraft sent to the surface of Mars have failed, so we know we have our work cut out to get down safely at Jezero."

Perseverance will enter the Martian atmosphere on Thursday evening UK time.

It will plunge into Mars' thin air at more than 20,000km/h (12,500 mp/h) and it will have to reduce speed to a near-walking pace by the time it reaches the surface.

The robot's protective shell and heat shield will do most of the work of slowing down the entry through Mars' atmosphere, but a supersonic parachute and a rocket jetpack, or "Sky crane", will be needed for the last three minutes of braking and landing.